Soybean – The Interesting Legume

Soybean is an interesting plant. It provides a valuable protein source for human and animal consumption, it is an important feedstock for biodiesel production, and it interacts with soil-borne bacteria (Rhizobia) that capture atmospheric nitrogen and store it in the soil, a beneficial side-effect utilized during crop rotation. In an effort to unlock the full power of this plant, scientists have sequenced the soybean genome.

“Most people are familiar with sequencing of the human genome,” begins Jeremy Schmutz, faculty scientist at Hudson Alpha Institute for Biotechnology, a partner laboratory with the DOE Joint Genome Institute (JGI). “The soybean genome was sequenced to provide scientists a better understanding of plant productivity, complex biochemical pathways, such as oil production, and pest and pathogen resistance just like the human genome is helping scientists to understand human diseases.”

The scientific team, led by Schmutz, used a process called “whole genome shotgun” to sequence the entire genome as a single effort. “With this technique, we were able to sequence and order the genome at one time so the scientific community could go directly from the genome sequence to breeding new varieties of soybean” said Schmutz.

At first glance, the soybean genome is an impressive size - 1,115 mega -base pairs (Mbp) (1,115,000 base pairs) – about 1/3 the size of the human genome, which contains approximately 3,000 Mbp. But by plant standards, the soybean genome is relatively small and tractable for genomics research.

The soybean genome, like other plant genomes, displays a feature called polyploidy. Schmutz explains, “During seed generation, whole regions of the genome can be duplicated. These duplications can infer a competitive advantage to the plant allowing it to thrive.”